*8 PSK TRANSMITTER

2 to 4 level converters - are parallel input DAC
Q or I - determines the polarity of the voltage (+V or -V)
C - determines the magnitude of the voltage (1.307 or 0.541 )

    Note : Logic 1 = +V
               Logic 0 = -V
               Logic 1 = 1.307 V
               Logic 0 = 0.541 V

Example : To transmit 000
                    Q =0 : I = 0; C =0

• For the I channel the input for the 2 to 4 converter are I=0 meaning a -V and C= 0 meaning 0.541 V. Hence output =- 0.541 Volts
• At the upper product modulator the output multiplied with the carrier will yield I =-0.541sin wct
• For the Q channel, the input for the 2 to 4 converter are Q=0 meaning -V and C' = 1 meaning 1.307. Hence, the output =-1.307.
• At the lower product modulator, the output will be the product of the 900 shifted carrier which is coswct and the output of the 2 to 4 converter. Therefore, it will yield Q =-1.307 coswct.
• The 8 PSK Transmitter output will be added by the linear summer as:

8PSK output = -0.541 sinwct -1.307cos wct

but the combination of two sinusoidal forcing :

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